docs: def lon_bounds(self):
          """Longitude of grid interfaces (degrees)
  
          :getter:    Returns the bounds of axis ``'lon'`` if availible in the
                      process's domains.
          :type:      array
          :raises: :exc:`ValueError`
                      if no ``'lon'`` axis can be found.
  
          """
          try:
              for domname, dom in self.domains.items():
                  try:
                      thislon = dom.axes['lon'].bounds
                  except:
                      pass
              return thislon
          except:
              raise ValueError('Can\'t resolve a lon axis.')